Limitations of the unified Libraries

I just noticed that the iPhoto 9.3 and Aperture 3.3 libraries are not yet fully compatible: For some products, like slide shows, you are bound to the applications that you edited them with. You can browse them with either applications, but edit them only in one of them: You cannot edit iPhoto Books in Aperture, and iPhoto slideshows you can edit in Aperture, but never again in iPhoto. I found no documentation on what is fully compatible, and what can only be browsed in either application. So for some tasks (books, slide shows) it will still be important to decide in advance which application to use to create the product.